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激光诱导荧光技术与地下水重金属原位检测应用进展

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岩矿测试 2025年第1期44卷 19-34页

作者：毛康薛家奇陈卓张华中国科学院地球化学研究所环境地球化学国家重点实验室贵州贵阳550081

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水... 详细信息

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水重金属污染特性和无损获取其价态的优势。本文在简述LIF检测重金属原理和LIF原位检测地下水重金属装备基础上,重点从荧光探针合成及其在重金属传感检测方法的构建上总结了基于不同荧光探针的LIF现场检测重金属的研究进展。目前可用于重金属检测的荧光探针包括以小分子探针、有机大分子和聚集诱导发光为主的有机荧光探针和以金纳米簇、量子点和金属有机框架材料为代表的纳米荧光探针。这些探针的合成及其对应的传感检测方法的构建表明LIF技术在地下水重金属检测中具有巨大优势。而针对地下水重金属检测的LIF设备研发方面的成果虽不如荧光传感检测方法丰富,但已研制出部分重金属的传感器和检测装备,表现出良好的应用前景。未来研究将会聚焦在地下水重金属主控因子识别和抗干扰技术研发、荧光探针合成与LIF检测方法构建、重金属传感部件和检测装备集成研制,以及检测技术标准化,为后续场地地下水典型重金属LIF检测技术的研究提供参考。

关键词：地下水重金属激光诱导荧光荧光探针现场检测

Forward flight of a model butterfly: Simulation by equations of motion coupled with the Navier-Stokes equations

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Acta Mechanica Sinica 2012年第6期28卷 1590-1601页

作者： hua huang mao Sun Ministry-of-Education Key Laboratory of Fluid Mechanics. Beihang University

The forward flight of a model butterfly was stud- ied by simulation using the equations of motion coupled with the Navier-Stokes equations. The model butterfly moved under the action of aerodynamic and gravitational forces, where the aerodynamic forces were generated by flapping wings which moved with the body, allowing the body os- cillations of the model butterfly to be simulated. The main results are as follows：（1） The aerodynamic force produced by the wings is approximately perpendicular to the long-axis of body and is much larger in the downstroke than in the up- stroke. In the downstroke the body pitch angle is small and the large aerodynamic force points up and slightly backward, giving the weight-supporting vertical force and a small neg- ative horizontal force, whilst in the upstroke, the body an- gle is large and the relatively small aerodynamic force points forward and slightly downward, giving a positive horizon- tal force which overcomes the body drag and the negative horizontal force generated in the downstroke. （2） Pitching oscillation of the butterfly body plays an equivalent role of the wing-rotation of many other insects. （3） The body-mass- specific power of the model butterfly is 33.3 W/kg, not very different from that of many other insects, e.g., fruitflies and dragonflies.

关键词： Butterfly Forward flight - Unsteady aerody-namics - Equations of motion Navier-Stokes equations

On the Empty Essential Spectrum for Markov Processes in Dimension One

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Acta Mathematica Sinica,English Series 2006年第3期22卷 807-812页

作者： Yong hua mao Department of Mathematics Beijing Normal University

This paper gives characterizations for diffusion processes on the line and birth-death processes whose generators admit the empty essential spectra. Some equivalent conditions for empty essential spectra for general M... 详细信息

关键词： Markov generator Essential spectrum Compact embedding Hardy-type inequality

On the Diophantine System a^2+b^2=c^3 and a^x+b^y=c^z for b is an Odd Prime

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Acta Mathematica Sinica,English Series 2008年第6期24卷 917-924页

作者： mao hua LE Department of Mathematics Zhanjiang Normal College Zhanjiang 524048 P. R. China

Let a, b and c be fixed coprime positive integers. In this paper we prove that if a^2 ＋ b^2 = c^3 and b is an odd prime, then the equation a^x ＋ b^y = c^z has only the positive integer solution （x, y, z） = （2,2,3）.

关键词： exponential diophantine equation positive integer solution generalized Fermat conjecture

A Conjecture Concerning the Pure Exponential Diophantine Equation a^x+b^y=c^z

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Acta Mathematica Sinica,English Series 2005年第4期21卷 943-948页

作者： mao hua LE Department of Mathematics Zhanjiang Normal College Zhanfiang 524005 P. R. China

Let a, b, c, r be fixed positive integers such that a^2 ＋ b^2 = c^r, min（a, b, c, r）〉 1 and 2 r. In this paper we prove that if a ≡ 2 （mod 4）, b ≡ 3 （mod 4）, c 〉 3.10^37 and r 〉 7200, then the equation a... 详细信息

关键词： Pure exponential diophantine equation Number of solutions Completely determine

On Supercontractivity for Markov Semigroups

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Acta Mathematica Sinica,English Series 2007年第5期23卷 905-914页

作者： Yong hua mao School of Mathematical Science Beijing Normal University Beijing 100875 P. R. China

In this paper, we study the supercontractivity for Maxkov semigroups and obtain some sufficient and necessary conditions; especially explicit formulae are obtained for birth-death process and diffusion on the line. Sufficient conditions and necessary conditions in terms of isoperimetric inequalities are also presented. Moreover, we prove that the supercontractivity is equivalent to the compact embedding of Sobolev space into an Orlicz space.

关键词： Markov semigroup logarithmic Sobolev inequality supercontractivity compact embedding

L^P-Poincaré Inequality for General Symmetric Forms

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2055-2064页

作者： Yong hua mao School of Mathematical Science LMCS Ministing of Education Beijing Normal University Beijing 100875 P. R. China

Lp Poincare inequalities for general symmetric forms are established by new Cheeger＇s isoperimetric constants. Lp super-Poincare inequalities are introduced to describe the equivalent conditions for the Lp compact embedding, and the criteria via the new Cheeger＇s constants for those inequalities are presented. Finally, the concentration or the volume growth of measures for these inequalities are studied.

关键词： Lp Poincare inequality symmetric form isoperimetric constant compact embedding concentration

INFLUENCE OF STRUCTURE ON HYDRAULIC CHARACTERISTICS OF T SHAPE FISHWAY

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Journal of Hydrodynamics 2012年第5期24卷 684-691页

作者： mao Xi FU Jing-jing tuo You-cai AN Rui-dong LI Jia State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China HydroChina hua Dong Engineering Corp.9 Hangzhou 310014 China

While dams cut off the migratory route of fish, and affect their growth and breeding, fishways are built to restore the con- nectivity of rivers and facilitate the life cycle of these migratory fish. This paper proposes a new kind of fishway called the ＂T shape fishway＂, and studies it by using both numerical simulations and physical experimental methods with the aim to design a fishway in China for migratory fish with swimming and jumping capability much poorer, such as schizothorax davidi and schizothorax prenanti, as compared with migratory fish in other places of the world, like trout and salmon. It is indicated that the range of velocity in each regular pool of the T shape fishway is from 0.42 m/s to 1.22 m/s when the flow discharge Q is 350 L/s, and there are no large vortex zones found there. This study shows that the T shape fishway can meet the requirements of these migratory fish quite well in terms of velocity and flow patterns in China.

关键词： fishway migratory fish baffle drop sill numerical simulation experiment

Construction of Generalized Diffusion Processes: the Resolvent Approach

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Acta Mathematica Sinica,English Series 2020年第6期36卷 691-710页

作者： Ying LI Yong hua mao School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105P.R.China School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of EducationBeijing 100875P.R.China

In this paper,we define the generalized diffusion operator L=d/dMd/dS for two suitable measures on the line,which includes the generators of the birth-death processes,the one-dimensional diffusion and the gap diffusio... 详细信息

关键词： Generalized diffusion operator birth-death processes diffusion gap diffusion resolvent generalized diffusion processes